package org.apache.maven.plugin;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.util.List;

import org.apache.maven.model.Plugin;
import org.apache.maven.project.MavenProject;
import org.eclipse.aether.RepositorySystemSession;
import org.eclipse.aether.artifact.Artifact;
import org.eclipse.aether.graph.DependencyFilter;
import org.eclipse.aether.repository.RemoteRepository;

/**
 * Caches plugin artifacts. <strong>Warning:</strong> This is an internal utility interface that is
 * only public for technical reasons, it is not part of the public API. In particular, this
 * interface can be changed or deleted without prior notice.
 * 
 * @author Igor Fedorenko
 * @author Benjamin Bentmann
 */
public interface PluginArtifactsCache {

  /**
   * A cache key.
   */
  interface Key {
    // marker interface for cache keys
  }

  public static class CacheRecord {

    public final List<Artifact> artifacts;

    public final PluginResolutionException exception;

    public CacheRecord(List<Artifact> artifacts) {
      this.artifacts = artifacts;
      this.exception = null;
    }

    public CacheRecord(PluginResolutionException exception) {
      this.artifacts = null;
      this.exception = exception;
    }
  }

  Key createKey(Plugin plugin, DependencyFilter extensionFilter, List<RemoteRepository> repositories,
      RepositorySystemSession session);

  CacheRecord get(Key key) throws PluginResolutionException;

  CacheRecord put(Key key, List<Artifact> pluginArtifacts);

  CacheRecord put(Key key, PluginResolutionException e);

  void flush();

  /**
   * Registers the specified cache record for usage with the given project. Integrators can use the
   * information collected from this method in combination with a custom cache implementation to
   * dispose unused records from the cache.
   * 
   * @param project The project that employs the plugin realm, must not be {@code null}.
   * @param record The cache record being used for the project, must not be {@code null}.
   */
  void register(MavenProject project, CacheRecord record);

}
